automatic external batch number assignment

Hi gurus,

I'm facing to an huge issue.

I've created an subcontracting PO. Into this PO, I have inserted a external batch number to a component.

When I make a good receipt with MB0A transaction. movement type 101 for the finished product and movement type 543/O for component. the external batch number is populated in the material document. But I don't want the MB0A transaction populates this bactch number. I want to input it manually in this transaction.

Is it possible to disengage the automatic external batch number assignment by the MB0A transaction and insert a external batch number manually?

Thanks for your help.

L. YDIR